Edge-reinforced seamed belts

ABSTRACT

Seamed belts, in particular puzzle-cut imageable seam intermediate transfer belts and electrophotographic printing machines that use such transfer belts, that are resistant to unzipping. The seamed belts include a first substrate having a first end and a second end that mate to form a first seam that runs across the first substrate. Along at least one side edge of each end of the first substrate is a cut-out. With the first end and the second end mated to form the first seam the cut-outs align to form a larger cut-out. A second substrate is then fitted into the larger cut-out along a second seam. Beneficially, an adhesive is disposed over the first seam and the second seam. Imageable seam intermediate transfer belts have first and second substrates that are beneficially semiconductive and puzzle-cut seams.

FIELD OF THE INVENTION

This invention relates to seamed belts.

BACKGROUND OF THE INVENTION

Electrophotographic printing is a well-known and commonly used method ofcopying or printing documents. Electrophotographic printing is performedby exposing a light image representation of a desired document onto asubstantially uniformly charged photoreceptor. In response to that lightimage the photoreceptor discharges, creating an electrostatic latentimage of the desired document on the photoreceptor's surface. Toner isthen deposited onto that latent image, forming a toner image. The tonerimage is then transferred from the photoreceptor onto a receivingsubstrate such as a sheet of paper. The transferred toner image is thenfused with the substrate, usually using heat and/or pressure. Thesurface of the photoreceptor is then cleaned of residual developingmaterial and recharged in preparation for the production of anotherimage.

The foregoing generally describes black and white electrophotographicprinting machines. Electrophotographic printing can also produce colorimages by repeating the above process for each color of toner that isused to make the color image. For example, the photoreceptive surfacemay be exposed to a light image that represents a first color, sayblack. The resultant electrostatic latent image can then be developedwith black toner particles to produce a black toner layer that issubsequently transferred onto a receiving substrate. The process canthen be repeated for a second color, say yellow, then for a third color,say magenta, and finally for a fourth color, say cyan. When the tonerlayers are placed in superimposed registration the desired compositecolor toner image is formed and fused on the receiving substrate.

The color printing process described above superimposes the color tonerlayers directly onto a substrate, such as paper. Otherelectrophotographic printing systems use intermediate transfer belts. Insuch systems successive toner layers are electrostatically transferredin superimposed registration from the photoreceptor onto an intermediatetransfer belt. Only after the composite toner image is formed on theintermediate transfer belt is that image transferred and fused onto thesubstrate. Indeed, some electrophotographic printing systems usemultiple intermediate transfer belts, transferring toner to and frombelts as required to fulfill the requirements of the machine's overallarchitecture.

In operation, an intermediate transfer belt is brought into contact witha toner image-bearing member such as a photoreceptor belt. In thecontact zone an electrostatic field generating device such as acorotron, a bias transfer roller, a bias blade, or the like createselectrostatic fields that transfer toner onto the intermediate transferbelt. Subsequently, the intermediate transfer belt is brought intocontact with a receiver. A similar electrostatic field generatingdevices then transfers toner from the intermediate transfer belt to thereceiver. Depending on the system, a receiver can be anotherintermediate transfer member or a substrate onto which the toner willeventually be fixed. In either case the control of the electrostaticfields in and near the transfer zone is a significant factor in tonertransfer.

Intermediate transfer belts often take the form of seamed beltsfabricated by fastening two ends of a web material together, such as bywelding, sewing, wiring, stapling, or gluing. While seamlessintermediate transfer belts are possible, they require manufacturingprocesses that make them much more expensive than similar seamedintermediate transfer belts. This is particularly true when theintermediate transfer belt is long. While seamed intermediate transferbelts are relatively low in cost, the seam introduces a discontinuitythat interferes with the electrical, thermal, and mechanical propertiesof the belt. While it is possible to synchronize a printer's operationwith the motion of the intermediate transfer belt such that toner is notelectrostatically transferred onto the seam, such synchronization addsto the printer's expense and complexity, resulting in loss ofproductivity. Additionally, since high speed electrophotographicprinters typically produce images on paper sheets that are cut from acontinuous paper “web,” if the seam is avoided the resulting unusedportion of the paper web must be cut-out, producing waste. Furthermore,even with synchronization the mechanical problems related to thediscontinuity, such as excessive cleaner wear and mechanical vibrations,still exist. However, because of the numerous difficulties withtransferring toner onto and off of a seamed intermediate transfer belt,in the prior art it was necessary to avoid toner transfer onto (and thusoff of) a seam.

Acceptable intermediate transfer belts require sufficient seam strengthto achieve a desired operating life. While that life depends on thespecific application, typically it will be at least 100,000 operatingcycles, but more preferably 1,000,000 cycles. Considering that a seamedintermediate transfer belt suffers mechanical stresses from belttension, traveling over rollers, moving through transfer nips, andpassing through cleaning systems, achieving such a long operating lifeis not trivial. Thus the conflicting constraints of long life andlimited topographical size at the seam places a premium on adhesivestrength and good seam construction.

A prior art “puzzle-cut” approach to seamed belts significantly improvesthe seam's mechanical strength. U.S. Pat. No. 5,514,436, issued May 7,1996, entitled “Puzzle Cut Seamed Belt;” U.S. Pat. No. 5,549,193entitled “Endless Seamed Belt with Low Thickness Differential Betweenthe Seam and the Rest of the Belt;” and U.S. Pat. No. 5,487,707, issuedJan. 30, 1996, entitled “Puzzle Cut Seamed Belt With Bonding BetweenAdjacent Surface By UV Cured Adhesive” teach the puzzle-cut approach.While the puzzle-cuts described in the forgoing patents improve a seam'sstrength, further improvements would be beneficial. In particular,puzzle-cut seamed belts are susceptible to unzipping. That is, forcesacross an end of a seam can cause the end puzzle-cut interlock toseparate. Additional forces then cause the next puzzle-cut interlock tofail, and so on as the puzzle-cut seam unzips.

For a seamed intermediate belt to be acceptable, the final imageproduced from across the seam must be comparable in quality to imagesformed across the remainder of the belt. This is a difficult task due toa number of interrelated factors. Some of those factors relate to thefact that the seam should not greatly impact the electrostatic fieldsused to transfer toner. However, electrostatic transfer fields arethemselves dependent on the electrical properties of the intermediatetransfer belt. While this dependency is complex, briefly there areconditions where transfer fields are very sensitive to the resistivityand thickness of the materials used for the various layers of theintermediate transfer belt. Under other conditions the electrostatictransfer fields are relatively insensitive to those factors. Similarly,there are conditions where the electrostatic transfer fields are verysensitive to the dielectric constants of the materials used for thelayers of the intermediate transfer belt, and other conditions where theelectrostatic transfer fields are insensitive to the dielectricconstants. Therefore, to successfully transfer toner onto and off of aseamed intermediate transfer belt the electrical properties across andaround the seam should be carefully controlled to produce a properrelationship with the remainder of the belt. Since the electricalproperties depend on the interrelated factors of seam geometry, seamconstruction (such as adhesive beyond the seam), seam topology, seamthickness, the presence of an overcoating, and various other factorsthose factors should be taken into consideration for a givenapplication.

From above it can be seen that a seam's topography is very important ifone wants to transfer toner onto and off of a seam region withoutsignificant degradation of the final image. The seam topography includesnot only the seam itself, but also any overflow of the adhesive used inthe seam. This overflow can occur on both the toner-bearing side and theback-side of the belt. Adhesive overflow is important because the beltseam strength can depend upon on that overflow. However, excessiveoverflow increases various mechanical, electrical, and xerographicproblems. Furthermore, the adhesive's electrical properties are aconcern.

More information regarding imageable seam intermediate transfer beltscan be found in U.S. Ser. No. 09/460,896, U.S. Pat. No. 6,245,402,entitled “Imageable Seam Intermediate Transfer Belt Having An Overcoat,”by Edward L. Schlueter, Jr. et al., and U.S. Ser. No. 09/460,821, U.S.Pat. No. 6,261,659, entitled “Imageable Seam Intermediate TransferBelt,” by Gerald M. Fletcher et al., both filed on Dec. 14, 1999. Thosepatent documents discuss, among other things, “short-wavelength” and“long-wavelength” spatial disturbances, conformable overcoats, Paschenair breakdown, transfer nip air gaps, suitable electrical properties,material layers, material compositions, environmental and agingconcerns, cleaning, surface friction, and “set point control” approachesto enable wider tolerances in electrical properties.

The present invention specifically relates to improving a seam'smechanical properties without significantly degrading the otherdesirable properties of the belt, particularly when that belt is animageable seam intermediate transfer belt. As previously indicated,prior art puzzle-cut seams have a tendency to unzip. Therefore, a seamedbelt with improved resistance to unzipping would be beneficial. Evenmore beneficial would be a puzzle-cut belt that is resistant tounzipping. Even more beneficial would be a puzzle-cut, imageable seamintermediate transfer belt that is resistant to unzipping.

SUMMARY OF THE INVENTION

The principles of the present invention provide for seamed belts thatare resistant to unzipping, in particular, puzzle-cut imageable seamintermediate transfer belts that find use in marking machines. A seamedbelt according to the present invention includes a first substratehaving a first end and a second end that mate to form a first seam thatruns across the substrate. Along at least one side edge of each end ofthe first substrate is a cut-out. With the first end and the second endmated to form the first seam the cut-outs align to form a larger cut-outsuch that the first seam begins at the larger cut-out. A secondsubstrate is then fitted into the larger cut-out along a second seam.Beneficially, an adhesive is disposed over the first seam and the secondseam. If the seamed belt is an imageable seam intermediate transfer beltthe first and second substrates are beneficially semiconductive and theseams are beneficially puzzle-cut. Furthermore, it may be beneficial toinclude cut-outs on each side edge of each end of the first substratesuch that forming the first seam produces two larger cut-outs, one oneach side of the first substrate, with the first seam running betweenthe two larger cut-outs. Then, a second substrate is fitted into one ofthe larger cut-outs along a second seam and a third substrate is fittedinto the other larger cut-out along a third seam. If the seamed belt isan imageable seam intermediate transfer belt the substrates are allbeneficially semiconductive and all of the seams are beneficiallypuzzle-cut. Preferably, imageable seam intermediate transfer beltsaccording to the principles of the present invention find use inelectrophotographic printing machines.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features of the present invention will become apparent as thefollowing description proceeds and upon reference to the drawings, inwhich:

FIG. 1 is an isometric representation of a puzzle-cut seamedintermediate transfer belt that is in accord with the principles of thepresent invention;

FIG. 2 is a close-up, top down view of puzzle-cut tabs as used in thebelt of FIG. 1;

FIG. 3 shows puzzle-cut tabs shown in FIG. 2 interlocked with a matchingedge to form a kerf;

FIG. 4 shows the puzzle-cut tab of FIG. 3 with the kerf filled with anadhesive;

FIG. 5 illustrates a close-up view of a seam mating area highlighted inFIG. 1;

FIG. 6 illustrates an electrophotographic printing machine that uses aseamed intermediate transfer belt that is in accord with the principlesof the present invention; and

FIG. 7 illustrates a more detailed view of part of theelectrophotographic printing machine illustrated in FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

While the principles of the present invention are described below inconnection with an imageable seam intermediate transfer belt, and itsapplication in an electrophotographic marking machine, it should beunderstood that the present invention is not limited to thoseembodiments. On the contrary, the present invention is intended to coverall alternatives, modifications, and equivalents as may be includedwithin the spirit and scope of the appended claims.

An imageable seam intermediate transfer belt 8 that is in accord withthe principles of the present invention is illustrated in FIG. 1. Thatbelt includes a semiconductive substrate layer 10 that has its endsjoined together to form a continuous belt using mechanically interlocked“puzzle-cut” tabs that form a seam 11. Furthermore, the imageable seamintermediate transfer belt 8 includes a second substrate 13 that matesto the remainder of the belt along a puzzle-cut seam 14 and a thirdsubstrate 15 that joins to the remainder of the belt along a puzzle-cutseam 16. Reference U.S. Pat. Nos. 5,487,707; 5,514,436; 5,549,193; and5,721,032 for additional information on puzzle-cut patterns. Typicallythe seam 11 is about ¼ inch wide.

The imageable seam intermediate transfer belt 8 is thus formed fromthree substrates, the substrates 10, 13, and 15, with the substrates 10and 13 joined by the seam 14 and the substrates 10 and 15 joined by theseam 16. The imageable seam intermediate transfer belt 8 is beneficiallymade by forming puzzle-cut patterns on each end of the substrate 10.Then, along each side edge of each end of the substrate 10 there isformed a cut-out having puzzle-cut edges. Then, the first end and thesecond end of the substrate 10 are mated to form a larger cut-out oneach side of the belt. The substrate 13 having puzzle-cut tabs that matewith the puzzle-cut patterns on one side of the substrate is then placedin one cut-out while the substrate 15, having puzzle-cut tabs that matewith the puzzle-cut patterns on the other side of the substrate is thenplaced in its cut-out. An adhesive is then disposed over the seams 11,14, and 16.

The substrates 10, 13, and 15 can be made from a number of differentmaterials, including polyesters, polyurethanes, polyimides, polyvinylchlorides, polyolefins (such as polyethylene and polypropylene) and/orpolyamides (such as nylon), polycarbonates, or acrylics, or blends oraloys of such materials. Beneficially, all of the substrates are madefrom the same material. If required, the selected material is modifiedby the addition of an appropriate filler such that the substrate layerhas a desired electrical conductivity. Appropriate fillers can include,for example, carbon, Accufluor® fluorinated carbon black, and/orpolyanaline, polythiophene or other conductive fillers or polymers.Donor salts can also be used. The substrate layer material should havethe physical characteristics appropriate to an intermediate transferapplication, including good tensile strength (Young's modulus, typically1×10³ to 1×10⁶ Newton's/m², resistivity (typically less than 10¹³ ohm cmvolume resistivity, greater than 10⁸ ohms/square lateral resistivity),thermal conductivity, thermal stability, flex strength, and hightemperature longevity. See the previously referenced U.S. patentapplications Ser. No. 09/460,896, U.S. Pat. No. 6,245,402, entitled“Imageable Seam Intermediate Transfer Belt Having An Overcoat,” byEdward L. Schlueter, Jr. et al., and Ser. No. 09/460,821, U.S. Pat. No.6,261,659, entitled “Imageable Seam Intermediate Transfer Belt,” byGerald M. Fletcher et al., both filed on Dec. 14, 1999.

FIG. 2 shows a top view of a puzzle-cut tab pattern. That pattern iscomprised of tabs that are comprised of a neck 18 and a node 20. Theshape of the tabs defines female interlocking portions 22. The tabs oneach end are dimensioned to interlock. The puzzle-cut tabs may be formedusing any conventional shaping technique, such as die cutting, orcutting wheels, or laser cutting, specifically using a lasermicro-machining system.

FIG. 3 shows a top view of the puzzle-cut tabs of FIG. 2 interlockedtogether. The shape of the interlocking tabs reduce stressconcentrations along the seam (seam 11 shown in FIGS. 3 and 4) andpermit easy travel around curved members, such as rollers 12 as shown inFIG. 1. Physically interlocking the puzzle-cut tabs may require pressurewhen mating. The interlocking tabs produce a gap between the mutuallymating elements that is called a kerf 24. The gap arises because of thedifference between the necks 18/nodes 20 and the female interlockingportions 22. As shown in FIG. 4 the interlocking tabs are held togetherusing an adhesive 26 that fills the kerf. The adhesive is designed to bephysically, chemically, thermally, mechanically, and electricallycompatible with the substrate layer material(s). Seams with a 25 micronkerf have been typical for puzzle-cut seams, while a kerf less thanabout 5 microns is generally preferred. Significantly, the adhesive andthe puzzle-cut tabs act together to create a strong seam. Ideally theseam should be strong, smooth, and mechanically uniform.

The adhesive 26 should have a viscosity such that it readily wicks intothe kerf. Additionally, the surface energy of the adhesive should becompatible with the substrate layer material such that the adhesiveadequately wets and spreads. Furthermore, the adhesive should remainflexible and should adhere well to the substrate layer material.Finally, the adhesive also should have low shrinkage during curing. Asan example, the adhesive can be a hot melt adhesive that is heated andpressed into the seam such that the adhesive is flattened, making it asmechanically uniform as possible with the substrate layer 10.Alternatively, the adhesive can be an epoxy-like material, a UV curableadhesive including acrylic epoxies, polyvinyl butyrals, or the like.Further, the “adhesive” can be substantially the substrate materialitself, either applied during a separate adhesive application step orelse by melting the two ends sufficiently to cause adhesion of themutually mating elements. Finally, the adhesives may be electricallymodified as required for the particular application. Following theapplication of the adhesive the seam 11 can be finished by buffing,sanding, or micro polishing to achieve a smooth topography.

The relative electrical properties of the adhesive and the substratematerials are very important because they significantly affect thetransfer characteristics of the resulting seam as compared to thetransfer characteristics of the rest of the belt. Therefore, theadhesive should produce seams that have electrical properties thatcorrespond to that of the substrate material(s). That is, underoperating conditions a seam should create an electrostatic transferfield in the toner transfer zones that is within at least 20%,preferably within 10%, of the electrostatic transfer field that ispresent for the remainder of the belt. Ideally the seam electricalproperties are substantially the same as the substrate material(s) andhave substantially the same electrical property dependence as thesubstrates on all important factors, such environment, applied field,and aging. However, significant differences in electrical properties canbe allowed for some imageable seam conditions as discussed subsequently.The adhesive electrical properties can be met by mixing fillers oradditives with an adhesive. For example, an adhesive might containsilver, indium tin oxide, CuI, SnO2, TCNQ, Quinoline, carbon black, NiOand/or ionic complexes such as quaternary ammonium salts, metal oxides,graphite, or like conductive fillers and conductive polymers such aspolyanaline and polythiophenes.

Compared to prior art puzzle-cut seamed intermediate transfer belts, abelt according to the present invention has improved resistance tounzipping. Referring now to FIG. 1, in the prior art, forces 26 and 28along an edge of the belt previously tended to unzip the seam 11.However, the presence of the seam 14 and the substrate 13 significantlyreduces this tendency. FIG. 5 shows a more detailed view of therelationship between the substrates 10 and 13 and the seams 11 and 14.As shown, the seam 11 connects to the seam 14 at a location 30. Forces26 and 28 distribute across the seam 14. Of course, the other end of theseam 11 terminates similarly at the substrate 15 and the seam 16.

The imageable seam intermediate transfer belt 8 is beneficially formedby fashioning substrate 10 with puzzle-cut tabs along a first end and ona second end and with cut-outs on each side edge. Those cut-outs alsoinclude puzzle-cut tabs. The ends then interlock to form the seam 11while the cut-outs on each side of the belt align to form a largercut-out such that the seam 11 runs between the cut-outs on each side.The substrate 13, which has puzzle-cut tabs, is then fitted into one ofthe larger cut-outs, while the substrate 15 is fitted into the otherlarger cut-out. An adhesive is then disposed over the seams 11, 14, and16. Beneficially the substrates 10, 13, and 15 are of the same material.

An electrophotographic marking machine 100 that makes beneficial use ofthe imageable seam intermediate transfer belt 8 is illustrated in FIGS.6 and 7. With reference to those figures (primarily FIG. 6) theelectrostatographic printer 100 includes the imageable seam intermediatetransfer belt 8, which is driven over guide rollers 114, 116, 118, and120. The imageable seam intermediate transfer belt 8 moves in a processdirection shown by the arrow B. For purposes of discussion, theimageable seam intermediate transfer belt includes sections that will bereferred to as toner areas. A toner area is that part of theintermediate transfer belt that receives actions from the variousstations positioned around the imageable seam intermediate transferbelt. While the imageable seam intermediate transfer belt may havemultiple toner areas each toner area is processed in the same way.

A toner area is moved past a set of four toner image stations 122, 124,126, and 128. Each toner image station operates to place a unique colortoner image on the toner image of the imageable seam intermediatetransfer belt 8. Each toner image producing station operates in the samemanner to form developed toner image for transfer to the imageable seamintermediate transfer belt.

While the image producing stations 122, 124, 126, 128 are described interms of photoreceptive systems, they may also be ionographic systems orother marking systems that form developed toner images. Each toner imageproducing station 122, 124, 126, 128 has an image bearing member 130.The image bearing member 130 is a drum supporting a photoreceptor 121(see FIG. 7).

Turn now to FIG. 7, which shows an exemplary toner image producingstation. That image bearing station generically represents each of thetoner image producing station 122, 124, 126, 128. As shown, thephotoreceptor 121 is uniformly charged at a charging station 132. Thecharging station is of well-known construction, having charge generationdevices such as corotrons or scorotrons for distribution of an evencharge on the surface of the image bearing member. An exposure station134 exposes the charged photoreceptor 121 in an image-wise fashion toform an electrostatic latent image on an image area. The image area isthat part of the image bearing member which receives the variousprocesses by the stations positioned around the image bearing member130. The image bearing member may have multiple image areas; however,each image area is processed in the same way.

The exposure station 134 preferably has a laser emitting a modulatedlaser beam. The exposure station then raster scans the modulated laserbeam onto the charged image area. The exposure station 134 canalternately employ LED arrays or other arrangements known in the art togenerate a light image representation that is projected onto the imagearea of the photoreceptor 121. The exposure station 134 exposes a lightimage representation of one color component of a composite color imageonto the image area to form a first electrostatic latent image. Each ofthe toner image producing stations 122, 124, 126, 128 will form anelectrostatic latent image corresponding to a particular color componentof a composite color image.

The exposed image area is then advanced to a development station 136.The developer station 136 has a developer corresponding to the colorcomponent of the composite color image. Typically, therefore, individualtoner image producing stations 122, 124, 126, and 128 will individuallydevelop the cyan, magenta, yellow, and black that make up a typicalcomposite color image. Additional toner image producing stations can beprovided for additional or alternate colors including highlight colorsor other custom colors. Therefore, each of the toner image producingstations 122, 124, 126, 128 develops a component toner image fortransfer to the toner area of the imageable seam intermediate transferbelt 8. The developer station 136 preferably develops the latent imagewith a charged dry toner powder to form the developed component tonerimage. The developer can employ a magnetic toner brush or otherwell-known development arrangements.

The image area having the component toner image then advances to thepretransfer station 138. The pretransfer station 138 preferably has apretransfer charging device to charge the component toner image and toachieve some leveling of the surface voltage above the photoreceptor 121to improve transfer of the component image from the image bearing member130 to the imageable seamed intermediate transfer member 8.Alternatively the pretransfer station 138 can use a pretransfer light tolevel the surface voltage above the photoreceptor 121. Furthermore, thiscan be used in cooperation with a pretransfer charging device.

The image area then advances to a transfer nip 140 defined between theimage bearing member 130 and the imageable seam intermediate transferbelt 8. The image bearing member 130 and imageable seam intermediatetransfer belt are synchronized such that each has substantially the samelinear velocity at the first transfer nip 140. The component toner imageis then electrostatically transferred from the image bearing member 130to the imageable seam intermediate transfer belt by use of a fieldgeneration station 142. The field generation station 142 is preferably abias roller that is electrically biased to create sufficientelectrostatic fields of a polarity opposite that of the component tonerimage to thereby transfer the component toner image to the imageableseam intermediate transfer belt. Alternatively the field generationstation can be a corona device or other various types of fieldgeneration systems known in the art. A prenip transfer blade 144mechanically biases the imageable seam intermediate transfer belt 8against the image bearing member 130 for improved transfer of thecomponent toner image.

After transfer of the component toner image, the image bearing member130 then continues to move the image area past a preclean station 139.The preclean station employs a pre-clean corotron to condition the tonercharge and the charge of the photoreceptor 121 to enable improvedcleaning of the image area. The image area then further advances to acleaning station 141. The cleaning station 141 removes the residualtoner or debris from the image area. The cleaning station 141 preferablyhas blades to wipe the residual toner particles from the image area.Alternately the cleaning station 141 can employ an electrostatic brushcleaner or other well-know cleaning systems. The operation of thecleaning station 141 completes the toner image production for each ofthe toner image producing stations.

Turning back to FIG. 6, the individual toner image producing stations122, 124, 126, and 128 each transfer their toner images onto theimageable seam intermediate transfer belt 8. A first component tonerimage is advanced onto the imageable seam intermediate transfer belt atthe transfer nip of the image producing station 122. Prior to the tonerarea arriving at that transfer nip the toner area is uniformly chargedby a conditioning station 146. This reduces the impact of any stray, lowor oppositely charged toner that might result in back transfer of tonerinto the image producing station 122. Such a conditioning station ispositioned before each transfer nip.

The toner images from the individual toner image producing stations 122,124, 126, and 128 are transferred such that the images are registered.That is, each of the individual color component images are transferredonto the imageable seam intermediate transfer belt 8 such that the humaneyes perceives a desired composite color image.

Turning now to both FIGS. 6 and 7, the imageable seam intermediatetransfer belt 8 then transports the composite toner image to apre-transfer charge conditioning station 152 that levels the charges atthe toner area of the imageable seam intermediate transfer belt andprepares them for transfer to a transfuse member 150. The pre-transfercharge conditioning station 152 is preferably a scorotron. A secondtransfer nip 148 is defined between the imageable seam intermediatetransfer belt 8 and the transfuse member 150. A field generation station142 and a pre- transfer nip blade 144 engage the imageable seamintermediate transfer belt and perform similar functions as the fieldgeneration stations 142 and pre-transfer blades 144 adjacent thetransfer nips 140. The composite toner image is then transferredelectrostatically onto the transfuse member 150.

The transfer of the composite toner image at the second transfer nip 148can be heat assisted if the temperature of the transfuse member 150 ismaintained at a sufficiently high optimized level and the temperature ofthe imageable seam intermediate transfer belt 8 is maintained at aconsiderably lower optimized level prior to the second transfer nip 148.The mechanism for heat assisted transfer is thought to be softening ofthe composite toner image during the dwell time of contact of the tonerin the second transfer nip 148. This composite toner softening resultsin increased adhesion of the composite toner image toward the transfusemember 150 at the interface between the composite toner image and thetransfuse member. This also results in increased cohesion of the layeredtoner pile of the composite toner image. The temperature on theimageable seam intermediate transfer belt prior to the second transfernip 148 needs to be sufficiently low to avoid too high a toner softeningand too high a resultant adhesion of the toner to the imageable seamintermediate transfer belt. The temperature of the transfuse membershould be considerably higher than the toner softening point prior tothe second transfer nip to insure optimum heat assist in the secondtransfer nip 148. Further, the temperature of the imageable seamintermediate transfer belt 8 just prior to the second transfer nip 148should be considerably lower than the temperature of the transfusemember 150 for optimum transfer in the second transfer nip 148.

Turning now to FIG. 7, the transfuse member 150 is guided in a cyclicalpath by guide rollers 174, 176, 178, 180. Guide rollers 174, 176 aloneor together are preferably heated to heat the transfuse member 150. Theimageable seam intermediate transfer belt 8 and transfuse member 150 arepreferably synchronized to have the generally same velocity in thetransfer nip 148. Additional heating of the transfuse member is providedby a heating station 182. The heating station 182 is preferably formedof infra-red lamps positioned internally to the path defined by thetransfuse member 150. The transfuse member 150 and a pressure roller 184form a third transfer nip 186.

A releasing agent applicator 188 applies a controlled quantity of areleasing material, such as a silicone oil to the surface of thetransfuse member 150. The releasing agent serves to assist in release ofthe composite toner image from the transfuse member 150 in the thirdtransfer nip 186.

The transfuse member 150 preferably has a top most layer formed of amaterial having a low surface energy, for example silicone elastomer,fluoroelastomers such as Viton™, polytetrafluoroethylene,perfluoralkane, and other fluorinated polymers. The transfuse member 150will preferably have intermediate layers between the top most and backlayers constructed of a Viton™ or silicone with carbon or otherconductivity enhancing additives to achieve the desired electricalproperties. The back layer is preferably a fabric modified to have thedesired electrical properties. Alternatively the back layer can be ametal such as stainless steel.

A substrate 170 is then advanced toward the third transfer nip 186. Thesubstrate 170 is transported and registered by a material feed andregistration system into a substrate pre-heater 173. The substratepre-heater 173 includes a transport belt that moves the substrate 170over a heated platen. The heated substrate 170 is then directed into thethird transfer nip 186.

At the third transfer nip the composite toner image is transferred andfused to the substrate 170 by heat and pressure to form a completeddocument 172. The document 172 is then directed into a sheet stacker orother well know document handing system (not shown).

A cooling station 166 cools the imageable seam intermediate transferbelt 8 after the second transfer nip 148. A cleaning station 154 engagesthe imageable seam intermediate transfer belt and removes oil, toner ordebris that may be remain onto the imageable seam intermediate transferbelt. The cleaning station 154 is preferably a cleaning blade alone orin combination with an electrostatic brush cleaner, or a cleaning web.

While the foregoing is sufficient to understand the general operation ofelectrophotographic printing machines that use imageable seamintermediate transfer belts, practical systems are somewhat difficult toachieve. This is because imageable seam intermediate transfer belts thatproduce acceptable final images, such as the imageable seam intermediatetransfer belt 8, are subject to numerous electrical and mechanicalconstraints, limitations, and design problems. More detailed discussionsof those constraints, limitations, and design problems are found in U.S.Ser. No. 09/460,896, U.S. Pat. No. 6,245,402, entitled “Imageable SeamIntermediate Transfer Belt Having An Overcoat,” in U.S. Ser. No.09/460,821, U.S. Pat No. 6,261,659, entitled “Imageable SeamIntermediate Transfer Belt,” both filed on Dec. 14, 1999, and in U.S.Ser. No. 09/634,307, entitled “Electrophotographic Marking MachineHaving An Imageable Seam Intermediate Transfer Belt,” filed on Aug. 8,2000.

While this invention has been described in conjunction with specificembodiments, it is evident that many alternatives, modifications, andvariations will be apparent to those skilled in the art. Accordingly, itis intended to embrace all such alternatives, modifications andvariations that fall within the spirit and broad scope of the appendedclaims.

We claim:
 1. A seamed belt, comprising: a first substrate having a firstend and a second end that mate to form a first seam that runs acrosssaid first substrate, said first substrate further including a cut-outalong at least one side edge at each end of said first substrate,wherein said first end and said second end are mated to form said firstseam, and wherein said cut-outs align to form a larger cut-out; and asecond substrate fitted into said larger cut-out to form a second seam.2. A seamed belt according to claim 1, wherein an adhesive is disposedover said first seam and said second seam.
 3. A seamed belt according toclaim 1, wherein said first and second substrates are semiconductive. 4.A seamed belt according to claim 1, wherein said first end and saidsecond end are puzzle-cut.
 5. A seamed belt according to claim 1,wherein said second seam is puzzle-cut.
 6. A seamed belt according toclaim 1, wherein said first substrate further includes a cut-out alongboth side edges at each end of said first substrate, wherein saidcut-outs on a first side mate to form a first larger cut-out, whereinsaid cut-outs on a second side mate to form a second larger cut-out, andfurther including a third substrate fitted into said second largercut-out along a third seam.
 7. A seamed belt according to claim 6,wherein said third seam is puzzle-cut.
 8. An imageable seam intermediatetransfer belt, comprising: a first semiconductive substrate having afirst end and a second end that mate to form a first seam that runsacross said first semiconductive substrate, said first semiconductivesubstrate further including a cut-out along at least one side edge ateach end of said first semiconductive substrate, wherein said first endand said second end are mated to form said first seam, and wherein saidcut-outs align to form a larger cut-out; and a second semiconductivesubstrate fitted into said larger cut-out to form a second seam.
 9. Animageable seam intermediate transfer belt according to claim 8, whereinan adhesive is disposed over said first seam and said second seam. 10.An imageable seam intermediate transfer belt according to claim 8,wherein said first end and said second end are puzzle-cut.
 11. Animageable seam intermediate transfer belt according to claim 8, whereinsaid second seam is puzzle-cut.
 12. An imageable seam intermediatetransfer belt according to claim 8, wherein said first semiconductivesubstrate includes a cut-out along both side edges at each end of saidfirst semiconductive substrate, wherein said cut-outs on a first sidemate to form a first larger cut-out, wherein said cut-outs on a secondside mate to form a second larger cut-out, and further including a thirdsemiconductive substrate fitted into said second larger cut-out along athird seam.
 13. An imageable seam intermediate transfer belt accordingto claim 12, wherein said third seam is puzzle-cut.
 14. A markingmachine, comprising: a moving photoreceptor belt; a charging station forcharging said photoreceptor belt; an imaging station for exposing saidcharged photoreceptor belt so as to produce a latent image; a developerfor depositing toner on said latent image; a transfer station fortransferring said deposited toner onto a substrate, said transferstation including an intermediate transfer belt that receives toner fromsaid charging station; a fuser having a fusing member for receivingtoner from said intermediate transfer belt and for fusing saidtransferred toner to said substrate; and a cleaning station for cleaningsaid photoreceptor; wherein said intermediate transfer belt comprises: afirst semiconductive substrate having a first end and a second end thatmate to form a first seam that runs across said first semiconductivesubstrate, said first semiconductive substrate further including acut-out along at least one side edge at each end of said firstsemiconductive substrate, wherein said first end and said second end aremated to form said first seam, and wherein said cut-outs align to form alarger cut-out; and a second semiconductive substrate fitted into saidlarger cut-out to form a second seam.
 15. A marking machine according toclaim 14, wherein an adhesive is disposed over said first seam and saidsecond seam.
 16. A marking machine according to claim 14, wherein saidfirst end and said second end are puzzle-cut.
 17. A marking machineaccording to claim 14, wherein said second seam is puzzle-cut.
 18. Amarking machine according to claim 14, wherein said first semiconductivesubstrate includes a cut-out along both side edges at each end of saidfirst semiconductive substrate, wherein said cut-outs on a first sidemate to form a first larger cut-out, wherein said cut-outs on a secondside mate to form a second larger cut-out, and further including a thirdsemiconductive substrate fitted into said second larger cut-out along athird seam.
 19. A marking machine according to claim 18, wherein saidthird seam is puzzle-cut.